It is known to provide, for the treatment of fibrous material in the textile industry, a roller which is formed with one or more grooves in a screwthread or helical pattern and a sawtooth wire which is received in the grooves.
The wire can have a lower or foot portion which is of generally rectangular cross section and can fill the groove, the teeth, which are of sawtooth configuration, being integral with the foot or base portion and projecting beyond the periphery of the roller.
In such rollers, the sawtooth wire can be rolled into the thread-like groove so that the ribs separating the turns of the groove or separating the grooves from one another are plastically deformed as the wire is forced into the grooves so as to provide a force-fit in which the clamping force resulting from deformation of the ribs of the roller body seizes the sawtooth wire and holds it in place.
As a consequence, earlier techniques in the fabrication of such rollers have required a certain deformation of the material of the roller body. While such deformation is easily possible with a roll body composed of aluminum, when steel is used as the roller body the deformation of the intergroove ribs requires a significantly higher force than that required for the deformation of aluminum.
As a consequence, by and large, steel has been avoided as a material for the roller body. However, the use of aluminum for the roller body is disadvantageous because, during the setting of the sawtooth wire in the groove and the deformation of the ribs, there is insufficient stability of the aluminum body and an overall deformation of the latter can occur.